Magnetic head
According to one embodiment, there is provided a magnetic head for a three-dimensional magnetic recording/reproducing apparatus, the head executing reading from or writing to a recording medium, utilizing a magnetic resonance, the medium including stacked layers formed of magnetic substances having different resonance frequencies, the head comprising a spin torque oscillation unit and auxiliary magnetic poles. The unit is operable to simultaneously oscillate at a plurality of frequencies to cause the magnetic resonance, when reading or writing. The magnetic poles assist the unit, when reading or writing. Further, according to another embodiment, there is provided a recording magnetic head using a high-frequency assist method and comprising a microwave magnetic field applying unit and a recording magnetic pole. The unit executes writing to a recording medium, and is formed of a plurality of spin torque oscillation elements having phases thereof synchronized. The magnetic pole assists the writing.
1. A magnetic head for use in a three-dimensional magnetic recording/reproducing apparatus, the magnetic head executing a reading from or a writing to a magnetic recording medium, utilizing a magnetic resonance phenomenon of the magnetic recording medium, the magnetic recording medium including a plurality of stacked magnetic layers formed of magnetic substances having different resonance frequencies, each of the stacked magnetic layers including a recording track, comprising:
a spin torque oscillation unit which simultaneously oscillates at a plurality of frequencies to cause the magnetic resonance phenomenon of the magnetic recording medium, when the reading from or the writing to the magnetic recording medium is to be executed; and
auxiliary magnetic poles which assist the spin torque oscillation unit, when the reading from or the writing to the magnetic recording medium is to be executed.
2. The magnetic head according to claim 1 , wherein the magnetic head is a read magnetic head, wherein the spin torque oscillation unit is a TMR type oscillation unit.
3. The magnetic head according to claim 1 , wherein the magnetic head is a read magnetic head, wherein the spin torque oscillation unit comprises a plurality of spin torque oscillation elements connected in parallel with each other to oscillate with different frequencies.
4. The magnetic head according to claim 1 , wherein the magnetic head is a write magnetic head, wherein the spin torque oscillation unit is a CPP-GMR type oscillation unit.
5. The magnetic head according to claim 1 , wherein the magnetic head is a write magnetic head, wherein the spin torque oscillation unit comprises a plurality of spin torque oscillation elements connected in series to oscillate with different frequencies.
6. The magnetic head according to claim 1 , wherein the spin torque oscillation unit simultaneously oscillates at the plurality of frequencies to execute simultaneous reading or simultaneous writing from or to the recording tracks associated with all or some of the plurality of stacked magnetic layers in accordance with a relationship between each of the plurality of frequencies and each of the resonance frequencies of the plurality of stacked magnetic layers.